So you're saying whether a CLA requires copyright assignment or not is not important since it makes no practical difference? Sounds odd, it must make some difference.
You also suggest that you can give permission to re-licence without assigning copyright. I didn't think that was possible.
All I'm saying is that just like we don't paint all copyright licences with the same brush, that we don't lump all CLA's together and instead discuss specific features of CLA's that cause problems and those that don't. For example, Google's CLA seems fairly harmless, perhaps I'm missing something.